Search Documents

By Willis I. L, Stevens B. P J, Stroud W. J

The Early Proterozoic metamorphic rocks of the Broken Hill (BH) Block have been recently subdivided into sixteen formations and four groups (Willis et al., 1983b, Stevens et al., 1983). This stratigraphic subdivision has relied upon recognition of distinctive mapped rock units and "associations" of mapped rock units, which characterize particular lithostratigraphic units. The rock units and rock unit associations define local ordered sequences which can be compared and correlated, thereby establishing the stratigraphic succession. In the Clevedale homestead, Thackaringa, BH City, Bores Mine-Freyers mine, Silver King mine, and Brewery Well areas, coherent stratigraphic successions have been interpreted. These areas illustrate the regional variability of the stratigraphic succession and facies changes within individual stratigraphic units. Stratigraphic type sections are located in the Thackaringa, Bores Mine-Freyers mine, Silver King mine, and Brewery Well areas. The principles of stratigraphic interpretation applied in the BH Block can be used in other areas of Willyama Supergroup outcrop such as the Euriowie, Olary and Mount Painter Blocks. The general technique may also have applicability to other highly deformed and metamorphosed terrains.

Jan 1, 1983

Nickel WestÆs Kalgoorlie Nickel Smelter operates three Peirce-Smith converters, each processing 110 tonnes of matte per charge. The vessels are lined with chrome-magnesia refractory with a mouth traditionally constructed from steel liner plates, protected with cast refractory. Mouth refractory is damaged by molten material and the action of cleaning solid buildup off the mouth. Once damage has accumulated, the mouth must be frequently maintained with hot refractory gunning or a mouth leak may occur. Such a leak requires a 32 hour repair period. A converter mouth redesign program was undertaken with the aim of reducing the rate of mouth damage during operation, eliminating mouth leaks and shortening mouth replacement times during vessel rebuild periods. An overview of the redesign process and operational performance is contained herein.

Jan 1, 2005

Investigation on Sheelite Floatability by Particle Size Fraction

Sep 13, 2010

The preferred alternatives in heap design and their motivation are identified as- -normal heap leaching, to be generally applied wherever possible, - flooded vat leaching, to be appliedwhere wetted ore lacks adequate cohesion or if limited space necessitates it,- thin layer leaching, to be applied where deleterious vat chemistry necessitates it.A number of the following features would probably be incorporated in the optimization of normal local heap leach operations- pre-cyanidation - pre-agglomeration - retaining walls- staged (counter-current) heap treatment- control of calcium levels- reduced pH and trickler irrigation

Jan 1, 1984

of the multitude of physiographic problems of immediate interest in volcanic terranes, it is the origin of the magma forming the magnificent volcanoes that is perhaps the most mysterious. Unlike anywhere else on earth, the possible locations of magma production beneath the convergent margins are strongly limited in depth and areal extent. Yet the exact process by which magma is produced still stands elusive, even in light of tremendous gains in analytical and physical insight. The principal aim here is to discuss some of what has been revealed about the physics and chemistry of the origin and evolution of island are magmas.

Jan 1, 1987

By Firmin K

The Mt. Tom Price orebody of Hamersley Iron Pty. Limited consists of a folded hematite - shale sequence capped by a layer of goethite. Consequently, variations in iron content occur within the orebody, and as the overall grade is below that required to make specification products, selective mining must be carried out. A necessary preliminary to quality control'of products based on selective mining is the production of advance data, on the tonnages and grades of material to be expected in future mining areas. Bench plans showing zones of different grades and types of material anticipated are prepared from structural geological information. The grades of materials on a bench are essentially governed by the positions and attitudes of the shale bands. Quality control is exercised by blending different grades and types of material in primary crusher feed. Iron grade is the prime grade consideration although sometimes the level of phosphorus content must be considered. Pre-production grades Are determined from assay of samples taken from blasthole cuttings.

Jan 1, 1980

Current mine ventilation systems have evolved from simple, limited energy, series or multi split layouts motivated by low suction, slow running, surface fans. Concentration of coal production from fewer working places and ventilation splits, and varying needs, hazards and challenges, however, have led to substan- tial changes. Modern ventilation systems, therefore, are more complex, sometimes more interdependent on others, more energy intensive, and are founded on the use of multiple airways and greater suction, higher speed surface ventilators and often booster fans. Intensi- fication of output has resulted also in higher gas emission rates, the wide adoption of fire- damp drainage, and sometimes in particular problems such as spontaneous firedamp emissions. Some coal mines are subject to spontaneous outbursts of coal and firedamp. These and related matters and current practices and developments are leading to discernible trends, potential advances, and further changes in Practice.

Jan 1, 1983

By Grieveson P, Rajakumar V

The reduction of an ilmenite concentrate with coal at 1000, 1050 and 1100¦C was investigated using thermogravimetry and X-ray diffraction, optical microscopy and electron probe microanalysis of the product. The effects of temperature, coal particle size, addition of ferric chloride and preheating of the concentrate in argon on the reduction kinetics and mechanism were determined. The rate of reduction increased significantly with temperature and was enhanced by the addition of the catalyst. The morphology of the iron was primarily determined by the degree of weathering of the particle. Significant coarsening of iron was obtained in the dense particles by the addition of ferric chloride. The sequence of reduction and the enhancement in the rate of reduction by preheating the concentrate in an inert atmosphere are discussed.

Jan 1, 1991

By Sennitt C. M, Hartley J. S

The Twin Hills Gold Deposit is an example of a preserved, high level, epithermal system, with mineralisation introduced contemporaneous with deposition. The deposit is hosted within sediments of the Late Devonian to Early Carboniferous Saint Anns Formation, of Cycle 1 Drummond Basin stratigraphy, situated in central Queensland. Prior to epithermal activity in the Twin Hills region, a lacustrine fan delta depositional environment existed, together with minor tuffaceous activity. An and palaeo climate, with occasional periods of torrential rainfall, together with a basin with faulted margins, allowed alluvial fan prograda- tion. Cyclical repetitions of the fan indicate repeated faulting and seismic activity took place during deposition. Significant gold mineralisation was first intersected at Twin Hills by Metana Minerals NL in 1988, after drill testing a "blind" target outlined by geological mapping and bedrock geochemistry.

Jan 1, 1991

By Moffatt G

Approval to operate Longwall No. 7 at Appin Colliery in 1979 was granted pursuant not only to the usual statutory provisions, but also that an adequate means of drainage of methane gas be incorporated. A methane drainage plant was subsequently designed and constructed some two km from the pit top at the site of the Colliery main upcast and down cast shafts. Modern plants of this nature are completely automated using programmable controllers and computers to provide control and management reporting functions. Complex mechanical systems are installed to extract the gas and in handling and storage processes. Gas utilisation plants exist which can generate power from methane. These plants are further enhanced by harnessing waste heat produced in the generation process. The installation, automation control and monitoring of these plants incorporates many facets of engineering from high voltage power supply and computer technology to complex gas handling procedures used in gas compression storage.and generation of electric power.

Jan 1, 1982

By Dionne S, Goodwin F. E

Zinc-aluminium alloy cast matrix composites have been made by squeeze casting, pressure infiltration, spraying forming and stir casting. The overview describes composites made . with these processes. Improvements in properties compared to the conventional alloys are most significant at elevated temperatures. Since stir casting is the most economical viable route of producing composites, progress made in this area is particularly emphasised.

Jan 1, 1993

By Bayly MG, Harris JA

The current operational practice at the Territory Enterprises Pty, Limited uranium oxide plant,, and some aspects of researc$ and development work at Rum Jungle are outlined with pertinent comments on some overseas practices.

Jan 1, 1968

By Gunther L. M, Rich N

Remapping of the Burdekin Basin has resulted in the subdivision of the three formations (megafacies) previously recognised in the Late Devonian Dotswood Group. Nine dominantly volcaniclastic facies are now identified within the three megafacies, representing coastal plain, floodplain lake, alluvial plain, ephemeral lake and alluvial fan depositional environments. The Dotswood Group was deposited during a major regressive phase that began at the end of the Givetian, continued throughout the Frasnian and ended in the early Famennian.The proposed depositional model completes a southeasterly progradation of coastal plain facies over shoreline and nearshore marine facies established in the underlying Fanning River Group. Uplift and associated acid-intermediate volcanism to the south of the Burdekin Basin, resulted in the deposition of a volcanogenic alluvial fan facies locally preserved along the southwestern margin of the basin. Tuffs and ?ignimbrite were deposited in widespread floodplain lakes which lay behind the coastal plain. An alluvial plain traversed by southward flowing rivers, formed the northern margin of the basin.

Jan 1, 1990

The Olympic Dam smelter utilises Outokumpu Oy, flash smelting technology to produce blister copper direct from high grade copper concentrate.This paper describes the unit processes involved, including filtering/drying, materials handling, smelting, gas/dust handling, waste heat recovery, sulphur fixing, anode refining and casting.

Jan 1, 1993

By D Hodder, M Hoskins, A Rofe

Pasminco Century MineÆs slurry pipeline was commissioned in November 1999. It currently transports zinc and lead concentrate slurries in batch form to the Port facility, 304 km away in the Gulf of Carpentaria. The Pipeline and the Port have gone through several stages of continuous improvement to match the successful ramp-up of the concentrator. Improvements in the Pipeline and Port Operations have included: commissioning of the first slurry pipeline that delivers two products in the same pipeline in batch mode; management of batches throughout the pipeline and port system to minimise cross contamination of both concentrates; operation of the slurry pipeline to achieve high availability of the system; operation of the pump station interfaced with preventive maintenance to minimise unplanned shutdowns; continuous monitoring of pressures throughout the single-station, 304 km slurry pipeline; redesign of the Rotary screw feeder; redesign of the Dryer Control System; installation of a larger Induced Draft Fan; optimisation of the dryer internals to achieve a product of narrow size distribution and pellet integrity; redesign of the stockpile ventilation system; and the development of a surface sealant. This paper describes the early commissioning of both the Port and the Pipeline and the continuous learning and Quality Improvement Project initiated at the Port to focus on concentrate quality given the propensity of the fine concentrate to self-heat during storage.

Jan 1, 2003

The disadvantages of the present zinc producing methods, RLE and ISP, are high energy consumption and environmental problems. Therefore, efforts have been directed in Outokumpu Zinc towards the development of alternate routes. One interesting pyrometallurgical process to produce zinc is to inject zinc calcine together with a solid reductant into molten iron, saturated with carbon. This process has been studied by thermodynamic calculations, laboratory tests and mini-pilot test runs at Outokumpu Research Oy, Pori, Finland. The results of these tests are presented and discussed in this paper. The mini-pilot tests demonstrated that over 97 per cent evaporation of the zinc was possible using a reactive coal dust as the reducing agent. The recovery of zinc in the metal phase was at best 88 per cent of input zinc, but only part reported in molten lead in the splash condenser. The final metallic zinc contained at best 98 per cent Zn, the main impurities being dissolved lead and coal carried along with the flue dusts.

Jan 1, 1993

By A Radici, S Russell

The Dampier Port Upgrade was completed in 2007 and is the largest project in Rio Tinto Iron Ore's expansion program. The project doubled Dampier Port's iron ore shipping capacity over a five year period. Sinclair Knight Merz (SKM) was appointed by Rio Tinto as the Engineering, Procurement and Construction Management (EPCM) contractor to manage Phase A and Phase B of the Dampier Port Upgrade. The aim of the project was to increase the Dampier Port capacity from 74 to 140 million tonnes per annum (Mt/a). This increase in shipping capacity tripled the capacity of the Parker Point facility from 34 to 94 Mt/a, whilst the East Intercourse Island facility increased from 40 to 46 Mt/a. The Dampier port remained fully operational throughout construction and achieved record yearly export tonnages over the period of the project. The $US1.4B project was completed ahead of schedule, on budget and with an outstanding safety record. Significantly the project team set an industry benchmark by achieving five million man-hours Lost Time Injury (LTI) free. The project has been recognised by the Engineers Australia 2008 Western Australian Engineering Excellence awards as category winner in resources and the overall winner in WA, and went on to win a National Engineering Excellence award. This paper provides an overview of the EPCM project management and an insight into some of the key drivers that have delivered this outstanding project.

Jan 1, 2009

By Cutafani M, Lama R

An approach to combatting abnormal roof control conditions in underground coal mines is outlined. Support techniques available are discussed along with the methods available to be adopted in different situations. Properties of materials available presently are tabulated together with the conditions of their Application.

Jan 1, 1988

The preconcentration of uranium ore by radiometric ore sorting at Mary Kathleen Uranium Ltd. is described. The operation of the ore sorting machines is discussed in detail and performance results obtained with the existing system are presented.

Jan 1, 1978

Synthetic seismograms of reflectivity method and some field records available are studied to detect the amplitude anomalies at the interface of the gaothermal reservoir the gas and/or oil boundary, and the underground tunnel. The first arrival of PO wave on the P-SV record are weak and emergent while those of P wave only rotated with respect to an incident angle are clear. This can, be explained by means of the energy loss of P-SV wave conversion. The primary reflections of P waves about depth fade away as compared to SH waves which do not perform any conversion, although they hold high attenuation in the fully saturated fluid layers. Reflection of comparable strength is present at the P-wave and S-wave... boundaries, but gas-saturated zones correlating with P wave bright spots do not show equivalent attenuation anomalies. Thus the comparative technique of P-SV wave and SI i wave records is very useful to indicate the strong amplitude anomalies at the boundaries of sealing targets.

Jan 1, 1990